This rare kanji has no clear standalone meaning. Treat its meaning as uncertain.
灈 combines 氵 (water) with 瞿, which likely contributes the sound. The exact historical development is uncertain.
The water radical 氵 beside 瞿 suggests a connection to water, but the specific meaning is uncertain.
For ク, imagine a cool (クール) stream of water: cool -> ク, and the water radical 氵 reinforces the image.
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